Camera flashlight synchronizer



i 5,1938. E. w. KRUEGER 7 2,123,112

CAMERA FLASHLIGHT SYNCHRONIZER Filed April 28, 1937 2 Sheets-Sheet 1 v[Bugger July 5, 1 938 5. w. KRUEGER CAMERA FLASHLIGHT SYNCHRONIZER FiledApril 28, 1937 2 SheetsSheet 2 JWUCMM 17. W mueger Patented July 5, 1938UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to a. synchronizing attachment or mechanism forcameras or photographic apparatus and it aims to provide a novelapparatus dependent on and operable through motion of the shutteritself, to generally simplify such structures as a result andparticularly avoid a construction which is linked mechanically to theshutter release button, or requires intervention of the human element,and the attendant objections and uncertainties.

The more specific objects and advantages will become apparent from aconsideration of the description following taken in connection withaccompanying drawings illustrating an operative embodiment.

In said drawings:-

Figure 1 is a front elevation of one form embodying my improvements;

Figure 21s a view of the parts of Figure l, on a larger scale, andprimarily in vertical section;

Figure 3 is a plan view oithe synchronizing.

unit alone;

Figure 4 is an end elevation of such unit looking from the left ofFigure 3;

Figure 5 is a substantially central longitudinal sectional view throughthe said unit Figure 6 is a front elevation of a modified form;

Figure '7 is a vertical sectional view through said modified form;

Figure 8 is a front elevation of a second modified form, and

Figure 9 is a view in plan, and partly in section, of such secondmodified form.

Referring specifically to the drawings, a flashlight structure generallyof conventional form is shown at A. It has a casing Iii connected to ametallic base plate II which also supports a camera l2, specificallyshown as a Leica, although it may be of any desired type. The camera isconnected to the plate by means of a screw l3 fitting the tripod bushingof such camera I2.

An electric battery it is located within the casing Ill and has oneterminal grounded thereto. The fiash bulb is shown at I! in coactingrelation with a reflector 16. Such bulb may be of any preferred type,for instance having a maneslum salt adapted to be ignited through theclosing of an electric circuit therethrough from battery i4. Conductorsl1 and I. connect the flash bulb with the battery. It will be understoodthat the camera I2 has metallic parts grounded to the plate II and whichinclude the usual timing disc I! for the shutter of the camera. Suchtiming disc according to my invention is equipped with a contact orelectrode 20 which may be a metallic screw, screw threaded thereto.

Also in accordance with my invention, the

usual accessory clips 2i on the camera casing are slidably anddetachabiy engaged by the foot 22 of a bracket 23 from which a post orwall 24 rises. Said post has an opening therethrough surrounded by aring 25 of insulation and adjustably extending through said ring is ashaft 26 having screw threads 21. Discs 28 of insulation engage oppositesides of the post 24 and nuts 29 and 30 are tightened on the threads 21and against said discs or washers 28, the conductor 18 being clampedagainst the shaft 26 by means of the nut 30.

Said shaft 26 has a vertically disposed tubular portion 3i through whicha bolt 32 is rotatable but held frictionally against accidental turning.Rigid on said bolt is a disc 33. A contact 34 is provided with a nut 35engaging screw threads 36 on said bolt 32, said contact and disc beingon opposite sides of the tube or sleeve 31.

Said contact 34 is arranged so that it will be engaged by the contact 20and the timing disc IQ of the shutter of the camera l2. When suchcontact occurs, an electric circuit is closed through the battery l4 andthe flash bulb.

Attention is called to the fact that the disc 33 is preferablycalibrated on its upper surface in the same manner that the timing discis is calibrated, thus enabling the calibrations to be used in adjustingor setting the contact 34 at any desired position or angle with respectto the contact 20.

As a result of the construction described, it will be realized that thesynchronization is effected by a part in effect of the shuttermechanism, avoiding complicated electrical switch means mechanicallylinked to the shutter release button requiring very diflicult and exactadjustment and in addition resort to thehuman element. 7

By the present construction, the bulbs do not have to be fired todetermine by trial whether the flash occurs at the proper time.

It is to be understood that the construction described is by way ofexample only and that various changes may be resorted to within thespirit, scope and principle of the invention. For instance, for camerasof the type such as the Compur", the flashlight synchronizer consists ofa metallic ring 40 which slips friction tight over the lens mounting ofthat camera. Such ring 40 has .an arm Ii extending therefrom whichsupports an electrical binding post and contact 42 to which a conductorll, like that in the first form of the invention at II, is fastened.Ring is grounded to the camera and the shutter winding lever of thelatter is shown at 48. The

ring ll supports the contact 4! in a position directly over such shutterwinding lever and the latter has a contact 44 thereon. After saidwinding lever II is set or wound for an exposure, the synchronizercontact 4! is so placed that when the timing lever is put in motionclipping the shutter, it touches the stationary contact 42, thus closingthe circuit to the battery ll, as in the first form of the invention andthereby igniting the magnesium or the flash bulb ll.

When the camera is focused by turning the lens mount itself, as in thecase of a "Korelle or like camera, the synchronizer system is modifiedas shown in Figures 8 and 9. A bracket N is employed having a clampportion II which clamps or clasps on the lens supporting post of thecamera. A tongue l2 extends toward the shutter winding lever ll carryinga contact. II at N. Tongue It carries a binding post and contact I towhich a conductor like that at II is connected.

These contacts 54 and ll are connected in the electric circuit means asin the first form of the invention and the circuit is adapted to beclosed to ignite the flash bulb through the contact ll touching thecontact II.

I claim as my invention:-

l. In combination with a camera having a shutter mechanism including amovable element provided with a contact, a contact on the cameraengageabie by the first contact, a flashlight unit including a batteryhaving one side connected to one contact and the other side connected tothe other contact, a slidably adjustable bracket on the camera, a shaftcarried by the bracket, an ele ment carried by the shaft rotatable on anaxis at an angle to the longitudinal axis of the shaft, said elementcarrying the second mentioned contact.

2. In combination with a camera having a shutter mechanism including amovable element provided with a contact, a contact on the cameraengageable by the first contact, a flashlight unit including a batteryhaving one side connected to one contact and the other side connected.to the other contact, a slidably adjustable bracket on the camera, ashaft carried by the bracket, an element carried by the shaft rotatableon an axis at an angle to the longitudinal axis of the shaft, saidelement carrying the second mentioned contact, a disc carried by saidelement to coact with the shutter mechanism to set the position of thesecond mentioned contact.

3. In combination with a camera having a shutter mechanism including amovable element provided with a contact, a contact on the cameraengageable by the first contact, a flashlight unit including a batteryhaving one side connected to one contact and the other side connected tothe other contact, a bracket having a plate-like base, clips on thecamera adjustably mounting said base, a wall rising from the baseintermediate the side edges thereof, a shaft insulated from the wall andadjustably fastened transversely thereof, said shaft extending laterallybeyond the base and at its free end having a sleeve at a right angle toits longitudinal axis, an element rotatabiy mounted by said sleeve, saidelement carrying the second mentioned contact.

ELTON W. KRUEGER.

